Physical Sciences and Mathematics Commons^™

Performance Evaluation Of A Coupled Photovoltaic-Thermal Solar Powered Desalination Pilot System, Martin Chavarin

Open Access Theses & Dissertations

A pilot scale coupled photovoltaic-thermal solar powered desalination system was evaluated at the Brackish Groundwater National Desalination Research Facility (BGNDRF). The pilot system consisted of a 3-kW photovoltaic-thermal (PVT) solar panel array and a 2.3 kW photovoltaic (PV) array coupled with a 4 gal/min single-stage 4 membrane reverse osmosis (RO) desalination system. A heat exchange system was in place to provide simultaneous cooling for the PVT system and heating to the RO system feed water. This system was evaluated with three objectives in mind. The first objective was to identify whether cooling of the PVT panels resulted in a significant …

How Active Rainwater Harvesting May Help Reduce Nuisance Flooding: Flood Analysis And Social Barriers To Adoption, Isabel Lopez

Open Access Theses & Dissertations

As urbanization continues to expand, fewer pervious surfaces are available to help reduce stormwater runoff from rainfall. The impacts of urbanization are becoming evident through sunny day flooding - flooding that occurs in areas not designated by the Federal Emergency Management Agency (FEMA) as flood zones. Nevertheless, water accumulates in low-lying areas and compromises street intersections and other parts of neighborhoods. Some methods can help alleviate the impacts of unexpected heavy rains, such as passive and active rainwater harvesting. As a pilot study, in a selected area in the northeast of El Paso, the level of adoption (e.g., what percentage …

Thermal Behavior Of Plain And Fiber-Reinforced Rigid Concrete Airfield Runways, Arash Karimi Pour

Open Access Theses & Dissertations

The environmental condition and temperature gradient are important factors resulting in concrete airfield runways cracking during the time. Rigid concrete airfield runways experience different thermal gradients during the day and night due to changes in air temperature. Curling and thermal expansion stresses are the main consequences resulting in various types of cracking over the surface and thickness of concrete airfield runways and increasing maintenance costs. The curvature of concrete slabs increases with an increase in the temperature gradient which is amplified when runways open to traffic. Additionally, the combination of the curling and shrinkage stresses, in rare circumstances, can be …

Sulfonated Styrene Grafted Sebs/Abs Made By Additive Manufacturing For Ion Exchange Applications, Avianna Elaine Gallegos

Open Access Theses & Dissertations

An interpenetrating polymer network (IPN) for cation exchange applications was synthesized from a blend of styrene-ethylene/butylene-styrene (SEBS) and acrylonitrile butadiene styrene (ABS), which was 3D printed, grafted with crosslinked polystyrene (PS), and sulfonated. A method for styrene grafting was applied to reduce the damage to polymer phases caused by the sulfonation reaction. Styrene and divinylbenzene monomers were introduced to the IPN and induced with heat treatment to polymerize in situ. The graft copolymerization reaction was enhanced with varying quantities of benzoyl peroxide as a chemical initiator. The samples were subsequently sulfonated with chlorosulfonic acid in dichloroethane and functionalized for ion …

A Case Study In Design, Construction, And Operation Of A Meromictic Solar Pond In Texas, Usa, Bianca Paola Meneses Brassea

Open Access Theses & Dissertations

Over the last four decades, meromictic solar ponds have been the subject of limnological studies and engineering research. A case of practical interest is the salinity gradient solar pond (SGSP). SGSP science and technologies have been systemically advanced in El Paso, Texas. This dissertation aims to share lessons learned in designing, constructing, and operating the El Paso Solar Pond, a NaCl-based solar pond that achieved high-temperature performance over two decades, commencing in 1984. Many of the practical lessons learned have not been published and are thus not readily available in archival journals, and this contribution provides a remedy. The value …

Identifying Particulate Matter Spatial Variation In The El Paso Del Norte Region Using Land-Use Regression Modeling And Data Obtained From A Network Of Low-Cost Sensors, Leonardo Demetrio Vazquez-Raygoza

Open Access Theses & Dissertations

The emergence and rise in popularity of low-cost sensors for atmospheric observation aresetting a new precedent in identifying emission hotspots and providing high-resolution spatial and temporal data. Furthermore, low-cost sensors are becoming popular among institutions and the public, allowing community scientists to become more involved in air quality monitoring. However, concerns about the accuracy and precision of low-cost sensors have been questioned. Most recent research has focused on the utility of real-time monitoring and calibration requirements for these sensors. A low-cost monitoring project has deployed sensors in the El Paso del Norte region in low and high annual average daily …

Environmental Justice Issues And Sea Level Rise In Frontline Communties Along The Gulf Coast, Karla Michel Lopez

Open Access Theses & Dissertations

Sea level rise poses a great threat to coastal areas and our way of life. As flooding increases in frequency and intensity across the country, vulnerable populations become a target to its impacts. The U.S. dedicates much research to risk communication and climate change adaptation strategies; however, these coastal areas are home to a large percentage of underserved and underrepresented communities that can be challenging to meaningfully engage. The impacts of short-term sea level rise combined with long-term sea level rise will not only cause flooding, erosion, and intrusion of saltwater into freshwater resources but also increased financial consequences, such …

Identification And Evaluation Of Critical Transportation Infrastructure Resilience After Hydro-Meteorological Event, Herman Serrato

Open Access Theses & Dissertations

Modern civilization is dependent on essential infrastructure assets that allow society to function in today’s standards. Critical interdependent infrastructure such as transportation, communication, security, and public health are marvels of human innovation and an important aspect of civilization's evolution. Recent world events such as climate change have underlined the necessity to develop strategic plans to enhance the resilience of infrastructure. This study aimed to identify and evaluate the flooding potential of critical transportation infrastructure that will influence traffic flow and impact the economy. The technical workflow is based on observations, predictions, experiments, testing, and analysis to derive a resilience score …

How The Pavement's Lifetime Depends On The Stress Level: An Explanation Of The Empirical Formula, Edgar Daniel Rodriguez Velasquez, Vladik Kreinovich, Olga Kosheleva, Hoang Phuong Nguyen

Departmental Technical Reports (CS)

We show that natural invariance ideas explain the empirical dependence on the pavement's lifetime on the stress level.

Application Of Machine Learning In Flood Depth Prediction, Armando Esquivel

Open Access Theses & Dissertations

Machine learning technologies have helped provide answers for problems with a high degree of complexity. Machine learning has been utilized by various disciplines within the Civil Engineering profession and has proven to be efficient in solving complex problems. Although machine learning is being used in the Civil Engineering profession, a formal framework on developing and integrating machine learning has not been developed for flood depth prediction. The proposed word uses machine learning to predict the depth of flood at Houston, TX, due to a 100-year 24-hour storm. The proposed work can be used to collect, store and analyze data to …

Digital Twin Technology Applications For Transportation Infrastructure - A Survey-Based Study, Hector Cruz

Open Access Theses & Dissertations

In the past couple of decades, various industries have taken advantage of emerging advanced technologies, such as digital twin (DT), to find more effective solutions in their respective areas. In the transportation infrastructure sector, the concept and implementation of DT technologies are slowly gaining traction but lagging behind other major industries. To better understand the limitations, opportunities and challenges for the adoption of DT in this sector, a survey questionnaire was distributed to collect information from industry professionals involved in transportation infrastructure projects. The purpose of this study is to understand how DT technology is being perceived by the industry. …

Life Cycle Studies To Evaluate The Physiological And Biochemical Effects Of Copper Oxide And Surface-Coated Titanium Dioxide Nanoparticles On Green Onion (Allium Fistulosum) And Carrot (Daucus Carota L.) Plants: Insights Utilizing Two-Photon Microscopy And Spectroscopy, Yi Wang

Open Access Theses & Dissertations

With the recent increase of nanomaterial production, nano copper oxide (nCuO) and surface-modified titanium dioxide nanoparticles (nTiO2) are among the most widely applied nanoparticles in industry and daily lives. Their use has resulted in accumulation in soils as a consequence of their direct or indirect release. Hence, these NPs may raise a potential risk to crops cultivated in soils. Moreover, the physiological effects of nCuO on green onion (Allium fistulosum) and surface-coated nTiO2 on full-grown carrot (Daucus carota L.) are still unknown. Green onion is characterized by its high content of the antioxidant allicin, and carrot is a worldwide economic …

Towards A Theoretical Explanation Of How Pavement Condition Index Deteriorates Over Time, Edgar Daniel Rodriguez Velasquez, Carlos M. Chang Albitres, Vladik Kreinovich

Departmental Technical Reports (CS)

To predict how the Pavement Condition Index will change over time, practitioners use a complex empirical formula derived in the 1980s. In this paper, we provide a possible theoretical explanation for this formula, an explanation based on general ideas of invariance. In general, the existence of a theoretical explanation makes a formula more reliable; thus, we hope that our explanation will make predictions of road quality more reliable.

Nonlinear Mechanical Properties Of Road Pavements: Geometric Symmetries Explain The Empirical Difference Between Roads Built On Clay Vs. Granular Soils, Afshin Gholamy, Vladik Kreinovich

Departmental Technical Reports (CS)

It is empirically known that roads built on clay soils have different nonlinear mechanical properties than roads built on granular soils (such as gravel or sand). In this paper, we show that this difficult-to-explain empirical fact can be naturally explained if we analyze the corresponding geometric symmetries.

A Comparative Study Characterizing Traffic Related Air Pollutant Concentrations At Near-Road Communities In El Paso, Texas, Adan Rangel

Open Access Theses & Dissertations

Numerous scientific studies have demonstrated the influence of traffic related air pollution at near-road communities and the associated health risks for these populations. This study uses on-site air quality monitors to characterize air pollutants at near-road schools in El Paso, TX to understand children's exposure to traffic-related air pollutants. Ambient air monitoring stations were installed at Coldwell Elementary, Bliss Elementary, and a residential house located in close proximity to major inter-state roadways. In this study, air quality data for PM2.5, PM10, NO2, and O3 was collected over a period of nine weeks in Fall 2018. The spatial and temporal variability …

Back Calculation Of Intelligent Compaction Data For Mechanical Properties Of Soil System, Afshin Gholamy

Open Access Theses & Dissertations

For national economy, it is very important to have a reliable infrastructure. Because of this, all over the world, new roads are constantly being built and old roads are being maintained and, if necessary, expanded and/or repaired. Building a good quality road is very expensive, it costs several million dollars per kilometer. It is therefore crucial to make sure that the newly built and newly repaired roads are sufficiently stiff - so that they can withstand the predicted volume of traffic for a sufficient number of years. Current methods of estimating the stiffness are time-consuming and labor-consuming. The most accurate …

Onshore-Offshore Velocity Models North Of The Mendocino Triple Junction In Northern California, Alan Jacquez

Open Access Theses & Dissertations

The Mendocino Triple Junction (MTJ) marks the boundary where the Gorda plate, North American Plate, and Pacific Plate meet, separating the Cascadia subduction zone to the North from transform tectonics of the San Andreas plate boundary. This actively deforming region experiences high seismic activity and young geological features. Here we examine offshore and onshore seismic wide-angle reflection and refraction data north of the MTJ crossing the Cascadia subduction zone from offshore northern California to the Western edge of the Sierra Nevada. We image subsurface structures in this region by creating P-wave velocity models using datasets collected in 1993 to 1994 …

Exploring The Effects Of Zinc Nanoparticle Concentration, Antioxidant, And Media On Cilantro (Coriandrum Sativum), And Radish (Raphanus Sativus) Plants Growth, Venkata Laxma Reddy Pullagurala

Open Access Theses & Dissertations

Engineered nanomaterials (ENMs) have proven to be one of the emerging chemicals of concern in the contemporary times. Soil acts as one of the major sinks of these ENMs. Reports have shown that ENMs have varied effects on soil biota. Particularly, their effects on plants are inconsistent. Amongst these ENMs, ZnO nanoparticles (nZnO) are the fourth largest raw materials in the nanotechnology industry. Globally, it is estimated that around 34,000 tons of n ZnO are utilized per year. The nZnO exposure on terrestrial plants yielded both beneficial as well as detrimental effects. Recently, there is an emerging evidence about the …

Effects Of Gradation And Moisture Content On Resistivity Of Mechanically Stabilized Earth Wall Backfill Materials, Jose Luis Arciniega

Open Access Theses & Dissertations

The service life of mechanically stabilized earth (MSE) walls depends on the corrosion rate of the metallic reinforcement used in their construction. The resistivity of the backfill aggregates needs to be measured accurately in order to estimate realistically the corrosion rate of the reinforcement. Resistivity testing is usually performed using the traditional soil box on the portion of the aggregates that passes a No. 10 or No. 8 sieve to either select or reject the backfill. For a more reasonable characterization of the corrosivity of coarse backfills, it is desirable to use their actual gradations. To that end, several resistivity …

The Former Asarco Demolition Fallout, A Post Study On Lead Soil Concentrations And Environmental Agents Of Redistribution In El Paso, Texas, Stephanie A. Robinson

Open Access Theses & Dissertations

The former El Paso ASARCO Smelting and Refining Co. operated between 1877 and 1999, the pyrometallurgic activity was estimated to have discharged excess of a 1,000 tons of lead (Pb) into the atmosphere from 1969-71. It was estimated 96 tons of (Pb) were emitted on an annual basis from the standing ore and fluid beds. The Environmental Protection Agency (EPA) determined that lead (Pb) is the heavy metal of the highest concentration within the vicinity of the smelter. After the smelter production ceased, flash flooding common to the southwest, such as the 2006 historic flood, increased transportation of superficial contaminants …

Studies Of Air Pollutants And Their Impact On Respiratory And Cardiovascular Diseases In The El Paso Del Norte Region With Emphasis On Mobile Emissions, Juan Gustavo Arias Ugarte

Open Access Theses & Dissertations

Air pollution may cause different diseases, such as cardiovascular and lung diseases. Traffic is a major source of mobile emissions causing air pollution. Exhaust emissions from mobile sources (Emissions of Carbon Monoxide, Nitrogen Oxides and Hydrocarbons) and Non-exhaust (Brake and Tire) are complex mixtures of gases and dust, including a large number of ultrafine particles, especially in areas with high traffic density. Recent studies have shown high rates of morbidity and mortality in people exposed to these types of emissions because the fine and ultrafine particles can be transported from the respiratory airways to the organs, thus contributing to increase …

Cost-Effective Recovery Of Concentrated Cooling Tower Blowdown Using The Cerro Process, Lindsey Nicole Larson

Open Access Theses & Dissertations

The Concentrate Enhanced Recovery Reverse Osmosis (CERRO) process is a seawater-RO unit that can cost-effectively achieve extremely high recoveries from water high in silica, carbonate and sulfate concentrations. This relatively new technology takes advantage of the induction time of potential foulants to recover more water than what is normally achievable with a conventional desalination system. The scope of the project was to evaluate the efficiency of the CERRO process as a pilot study using cooling tower blowdown which varied in water quality parameters daily. It was found that the CERRO pilot could successfully achieve 85% recovery, and the main limitation …

Minimizing Environmental Impacts For Hub And Spoke Distribution Network Problems Through The Use Of Multi-Objective Evolutionary Algorithms, Ileana Delgado

Open Access Theses & Dissertations

While transportation is crucial to our economy and our personal lives, as a sector it is also a significant source of greenhouse gas (GHG) emissions. The AASHTO report states, "America's transportation system has served us well, but now faces the challenges of congestion, energy supply, environmental impacts, climate change, and threatens the economic, social, and environmental future of the nation". With respect to the environment, transportation is the most visible aspect of supply chains. Transportation emissions can be reduced by implementing approaches that contribute to GHG emissions reduction, for example, the use of low-carbon fuels, new and improved vehicle technologies, …

A Novel Approach For Evaluating The Impact Of Fixed Variables On Photovoltaic (Pv) Solar Installations Using Enhanced Meta Data Analysis Among Higher Education Institutions In The United States, Diane N. De Hoyos

Open Access Theses & Dissertations

The global demand for electric energy has continuously increased over the last few decades. Some mature, alternative generation methods are wind, power, photovoltaic panels, biogas and fuel cells. In order to find alternative sources of energy to aid in the reduction of our nation's dependency on non-renewable fuels, energy sources include the use of solar energy panels. The intent of these initiatives is to provide substantial energy savings and reduce dependence on the electrical grid and net metering savings during the peak energy-use hours.

The focus of this study explores and provides a clearer picture of the adoption of solar …

Combining Interval And Probabilistic Uncertainty In Engineering Applications, Andrew Martin Pownuk

Open Access Theses & Dissertations

In many practical application, we process measurement results and expert estimates. Measurements and expert estimates are never absolutely accurate, their result are slightly different from the actual (unknown) values of the corresponding quantities. It is therefore desirable to analyze how this measurement and estimation inaccuracy affects the results of data processing. There exist numerous methods for estimating the accuracy of the results of data processing under different models of measurement and estimation inaccuracies: probabilistic, interval, and fuzzy. To be useful in engineering applications, these methods should provide accurate estimate for the resulting uncertainty, should not take too much computation time, …

National Evaluation For Development And Exploration Potential Of Mineral Commodities In Produced Waters, Stephanie Ray

Open Access Theses & Dissertations

The U.S. Geological Survey recently updated a geochemical database consisting of data for approximately 160,000 produced waters samples, primarily from petroleum and geothermal reservoirs. Using major and trace elements from conventional and unconventional well types from the database, this Thesis provides a comprehensive, national evaluation for mineral commodity potential in produced waters. Produced waters contain virtually every naturally occurring element and can range in salinity to several times that of seawater. Despite the typical outlook to view produced waters as a waste, they have potential for natural resource development.

This Thesis provides, for each mineral commodity found in the produced …

Effects Of Citric Acid Coated And Uncoated Cerium Oxide Nanoparticles In Tomato (Solanum Lycopersicum) Plants, Ana Cecilia Barrios

Open Access Theses & Dissertations

This research was performed to examine the physiological and biochemical effects of bare (nCeO2) and citric acid coated (nCeO2+CA) cerium oxide nanoparticles in tomato (Solanum lycopersicum). Plants were germinated and grown to full maturity in soil amended with 0-500 mg/kg and periodically analyzed using ICP-OES/MS and other spectroscopic and biochemical techniques. Although Ce in tissues increased as the external nCeO2 increased, there were no visible signs of toxicity. In mature plants, nCeO2 induced developmental changes and altered nutritional quality (essential elements) in fruits. On the other hand, nCeO2+CA affected fruit carbohydrate composition (sugars and starch). This study gives insights on …

Application Of Secondary Analyses On Industrial Data Sets, Luis G. Perez

Open Access Theses & Dissertations

Secondary analysis on quantitative data sets is the in-depth analysis of relationships, trends, patterns or behaviors that are not obvious from a superficial examination of data but that can be very germane in the application of that data. The present work presents a framework for investigators to use in applying secondary analysis on big data that correlates to the research topic. The framework can facilitate the illumination of possible data behaviors or patterns that could be useful in arriving at an answer to a question. Behavior of monitored equipment (analyzers, meters, etc.) can easily be depicted and can be used …

The Use Of Remote Sensing Technologies And Models To Study Pollutants In Pdn Region, Suhail Mahmud

Open Access Theses & Dissertations

Using a suite of modeling techniques and instrumentation we study the atmospheric pollutants in the PdN Region. The first objective of this work was to measure hemi-spherically integrated, spectrally resolved solar photon flux (actinic flux) between the wavelengths 300 and 700 nm, and use the measured actinic flux to improve air quality simulations. Actinic flux was measured in the PdN region in order to calculate photolysis rate coefficients for different pollutants. The improved photolysis rate coefficients were then integrated into a photochemical air quality model (CAMx) in order to improve air quality forecasting. We present the simulations performed for a …

A Decision Making Approach For Selection Of Sustainable Pavements In Texas By Integrating Life Cycle Cost Analysis (Lcca), Life Cycle Assessment (Lca) Of Environmental And Social Impacts, Sundeep Inti

Open Access Theses & Dissertations

A sustainable pavement can be defined as the one that minimally impacts future economic opportunities, social conditions, human health, and the environment and still fulfills the engineering objectives. Although a pavement as outlined above is not yet entirely feasible, continual effort from every stakeholder with a vision of achieving sustainable development is essential for the future of society. In this study, one such effort was initiated by proposing a framework for selection of pavement design based on sustainable development.

The concept of sustainability is widely believed to be founded on three criteria: economic, environmental, and social standards. Since the purpose …